The present invention relates to articles comprising a cell system with at least one cell filled with an active composition, the cell system further comprising a means for controlling the direction and flow of the cell""s contents, once said at least one cell has been ruptured.
Disposable articles comprising at least one capsule filled with an active composition associated to a substrate, for example a cotton pad are representative of the various articles to which the present invention can apply; such disposable articles typically comprise at least one capsule filled with an active composition, at least one element made out of an absorbent material. At the time the user breaks the capsules, their contents spreads onto the absorbent material and the disposable article is ready to use.
The following references are directed to such articles comprising a capsule system associated to an absorbent substrate: U.S. Pat. No. 4,878,775 (D1) is a U.S. patent to 3M. It discloses a device comprising burstable microcapsules containing a liquid, at least one sheet of a carrying substrate, and at least one sheet of a flexible liquid permeable material overlaying the microcapsules. Pressure on the device breaks the microcapsules and the liquid is dispensed on/through the liquid permeable sheet. U.S. Pat. No. 3,768,916 (D2) is a U.S. patent to Medical Supply Cy. It discloses a sponge comprising a hollow portion into which a glass ampoule is inserted. When the ampoule is broken by the user, the contained disinfectant soap impregnates the sponge for wound-cleaning use. U.S. Pat. No. 5,090,832 (D3) is a US patent to Colgate It discloses a disposable pad comprising a scrubber layer, a blotter layer of absorptive material and a liquid impervious sheet located between the scrubber and the blotter layers. The pad further comprises at least one packet containing sufficient cleaning material to saturate the scrubber layer when ruptured. FR 2,754,744 (D4) is a French patent application to A, Soares Duarte. It discloses a flexible film comprising cells filled with liquid. The cells are ruptured when pressure is exerted and the contained liquid is released and impregnates a support. DE 3,545,926 A1 (D5) is a German application to A. G. Frxc3xchauf. It discloses a system in which the capsules are made out of a material which does not rupture, but in which the seals between the two constitutive layers of said capsules are delaminated under pressure. Then, the cell contents is free to flow between said layers up to punctured holes through which it is dispensed. EP 0 294 189 A2 (D6) is a German patent application to Jaypak Ltd. It discloses a flexible bag combined to an absorbent applicator. The bag is burst to release the liquid inside the applicator.
None of the above documents D1 to D4 and D6 raises nor solves the problem of controlling the flow and direction of the cell""s contents to the outside medium, once the cell has been ruptured.
D5 discloses a cell system wherein the cells are not ruptured, but their constitutive layers are delaminated when the user exerts a pressure on the cell. The contents is then directed through channels created between the delaminated layers, up to holes punctured in one layer, through which it can escape to the outside. One disadvantage is: the way the layers delaminate is not predictable, and thus the direction of the contents is not predictable. Moreover, depending on the surface of delaminated film, the number of punctured holes which is accessible to the flowing contents can vary, is not predictable, and cannot be controlled.
It is therefore one main object of the present invention to provide the user with an article comprising a cell system with at least one cell filled with an active composition, the article further comprising a means for controlling the flow and direction of the cell""s contents, once said at least one cell has been ruptured.
The present invention is directed to a cell system with at least one burstable cell filled with an active composition, the cell system being characterized in that it comprises a means to control the flow and direction of the cell""s contents, once said at least one cell has been ruptured. More generally, the present invention is directed to an article which comprises such a cell system. Preferably, the cell system is associated with a dispersing element, such as for example a fibrous pad. Preferably, the force required to burst the cells is comprised within the range of 10 to 80 N. More preferably, the article is constructed so that less than 10% product is lost per year at 35xc2x0 C./20%RH, the barrier properties being achieved by selecting a barrier material for making either the cells, or an openable outer package hermetically closed around at least one article.